The present invention relates o the fluid sealing arts. More particularly, the present invention relates to a high-pressure rotary face seal for inhibiting fluid flow between a housing and a shaft which rotate relative to each other.
Mechanical face seals for use in rotary applications are well known. These seals are used in pumps, compressors, agitators, mixers, and a wide variety of other apparatus including a housing in which a shaft is supported for rotation. The face seals inhibit fluid flow between the housing and shaft.
While prior face seals have been found to be generally effective, they have not been found to be sufficiently long-lasting. This has necessitated their frequent replacement which results in down-time for the relevant apparatus. Even when these prior seals have been split to facilitate their removal from and installation on an associated shaft, at least, machine down-time is still significant.
Prior seals have been found to be relatively high-cost, unduly complex (e.g., multiple slits), and have also required relatively large amounts of space for installation. The complexity and space requirements have prevented such prior seals from being used in "closed" applications, i.e., applications where the seal must be installed inside of a fixed housing or the like where no access to the ultimate seal location is permitted. Thus, for example, these prior seals would not be usable in a "closed-groove" applications where a seal member must be installed in a grove circumscribing a shaft or the like, and wherein the shaft must then be axially inserted into a closed housing. Furthermore, in such closed-groove applications, multiple sealing points are often required (due to the presence of multiple fluid ports for communicating fluid from outside of the housing into passages extending through the shaft), and prior seals are not practical in such cases due to space, complexity, and cost considerations.
Another deficiency associated with known face seals is their diminished effectiveness at low fluid pressures. This results when low-pressure fluid is able to "seep" past the seal without engaging the seal and urging it into its operative sealing condition. Thus, for example, with prior seals, fluid is able to move past the seal for at least an initial period of time until sufficient fluid pressure is exerted on the seal to urge it into sealing engagement with the shaft or other component.
In light of the foregoing deficiencies and others associated with prior mechanical rotary face seals, it has been deemed desirable to develop a new and improved rotary face seal which overcomes these deficiencies and others while providing better and more advantageous overall results.